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Hydroxyproline is classified as a non-protein amino acid that is predominantly found in collagen, a vital protein that provides structure and strength to various tissues in the body, including skin, bones, and cartilage. The measurement of hydroxyproline levels can be significant in diagnosing and monitoring certain medical conditions. Elevated levels of hydroxyproline may indicate pathological conditions such as Paget's disease, which is characterized by abnormal bone remodeling, bone metastatic cancer, where cancer spreads to the bones, hyperparathyroidism, a condition that affects calcium levels in the body, osteoporosis, a disease that weakens bones, or glucocorticoid excess, which can affect various metabolic processes. Although hydroxyproline testing can serve as a non-specific marker for bone resorption, it is important to note that newer and more specific tests are now available. The accuracy of hydroxyproline test results can be influenced by dietary factors, particularly the ingestion of collagen, which may lead to elevated levels. For the CPT® Code 83505, the focus is on evaluating total hydroxyproline in urine. To ensure accurate results, patients are advised to adhere to a collagen-free diet for at least 72 hours prior to urine collection. The testing process involves collecting a 24-hour urine specimen, which is then analyzed using ion exchange chromatography or high-performance liquid chromatography (HPLC) to quantify the total hydroxyproline levels present in the urine.
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Hydroxyproline testing is indicated for the evaluation of various medical conditions that may lead to elevated levels of this amino acid in the body. The following conditions are explicitly associated with the need for this test:
The procedure for measuring total hydroxyproline in urine involves several critical steps to ensure accurate results. The following procedural steps are outlined:
After the urine collection and analysis, there are no specific post-procedure care instructions required for the patient. However, it is essential for healthcare providers to interpret the results in the context of the patient's overall clinical picture and any underlying conditions. Follow-up may be necessary based on the test results, particularly if elevated hydroxyproline levels are detected, as this may warrant further investigation or management of the underlying conditions associated with bone metabolism.
| Short Descr | ASSAY TOTAL HYDROXYPROLINE | Medium Descr | ASSAY OF TOTAL HYDROXYPROLINE | Long Descr | Hydroxyproline; total | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 1 | CCS Clinical Classification | 233 - Laboratory - Chemistry and Hematology |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. |
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| 2023-01-01 | Note | Medium description changed. |
| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2011-01-01 | Changed | Short description changed. |
| Pre-1990 | Added | Code added. |
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